USA Banner

Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #98-0345 ([Neal Langerman, Ph.D.])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name:

Individual Name: Neal Langerman, Ph.D.

Location State: CA Country: US

View the Interpretation Document

Response text:

MAR 18, 1999


Neal Langerman, Ph.D.                Ref No. 98-0345
8909 C Complex Drive
San Diego, CA 92123-1418

Dear Dr. Langerman:

This is in response to your letter and telephone conversations with a member of my staff regarding clarification of the requirements for shipping flameless ration heaters (FRH) in full pack (multiple) quantities or in single units as components of meals, ready-to-cat (NM),.and a previous letter dated July 7, 1992 to the Department of Defense (DOD) concerning classification of these items.  I apologize for the delay in responding and hope it has not caused any inconvenience.

The FR-H is a device packaged in a tough plastic envelope which, when water is added, generates heat to warm a field ration.  It is used in military meals, ready-to-eat (MRE), and each MRE includes one FRH. You indicated that the magnesium alloy contained in the FRH meets the definition of Division 4.3 (Dangerous When Wet).

Based on the information you provided, it is our determination that a single FRH device, containing eight grams of magnesium alloy or less packaged in a tough plastic envelope within an MRE, is in a quantity and form which does not pose a hazard in transportation and is not subject to the Hazardous Materials Regulations (HMR), regardless of the number of MRE’s in a package.  This determination does not apply to FRH devices shipped separately from MRE’s, or to FRH devices containing more than eight grams of magnesium alloy, which must be shipped in conformance to the applicable requirements of the HMR.

I hope this satisfies your inquiry.  If we can be of further assistance, please contact us.



Edward T. Mazzullo
Director, Office of Hazardous

Materials Standards


Regulation Sections

Section Subject
173.124 Class 4, Divisions 4.1, 4.2 and 4.3-Definitions